The olfactory system, including the main and accessory (vomeronasal) systems, is a component of the central nervous system known to proliferate throughout the life of the animal. The mouse vomeronasal epithelium detects odorants indicative of reproductive and social status. This detection occurs by a family of vomeronasal receptor (VR) genes which are G protein-coupled receptors (GPCRs). It is not known how the expression of these VR genes, and other genes across the whole genome, changes as the animal progresses from an early postnatal stage to aged adulthood. In addition, it is not known if the regenerative potential of the vomeronasal epithelium is altered as the animal ages. In the current proposal, I will use a custom microarray to examine how vomeronasal receptor gene expression changes in the vomeronasal epithelium over the lifespan of the mouse. I will also utilize a commercial Affymetrix array to monitor 37,000 other genes over the same time period with the goal of identifying those genes involved in the process of aging in the vomeronasal system. In addition, I will investigate whether the rates of proliferation and apoptosis are altered in the vomeronasal epithelium over all developmental stages. Finally, I will examine whether the vomeronasal epithelium regenerates with the same efficacy throughout the lifespan of the animal. This proposal seeks to identify those genes involved in the development and aging of a sensory tissue across the lifespan of the mouse. In addition, it will examine how this unique tissue renews itself over the course of that lifespan. These important experiments will inform us on how a tissue undergoes the process of aging, and possibly provide insights into how a tissue capable of reconstitution accomplishes this difficult process. [unreadable] [unreadable] [unreadable]